Pencil-sharpening machine



Oct. 22, 1929. R MARGUERAT 1,732,728

PENCIL SHARPENING MACHINE Filed May 21, 1927 Patented Oct. 22, 1929 PATENT i ROBERT MARGUERAT, OF MGNTROUG-E, FRANCE PENGIIi-SHARPENING MACHINE Application filed May 21, 1927, Serial No. 193,283, and in France May 26, 1926.

In the various methods of manufacturing` pencils, the sharpening of the pencils has been effected up to the present, by means of a cylinder on which is iiXed a sheet of sand paper t-he pencil being,r rubbed thereon While turning at great speed. The shaping1 of the coned end, that is the sliarpening is carried out by the relative rubbing of the extremity of the pencil on the sheet of sand paper, which latter has frequently to be replaced. Steel tools and in particular steel cutters employed for the operation have not given goed results in practice, as their edges are soon blunted by the impurities contained in the graphite, which rapidly attack the steel.

Sharpening means constructed according; to the present invention obviates these drawbacks by the employment of diamond cutters for the sharpening operation, which diamond experiments havingy tgiven most brilliant technical results.

The inventionhas for its object the following points:

1. The use of diamond cutters wherever possible in the manufacture of pencils.

2. The employment of a special automatic machine using;r these cutters, a machine characterized by the fact that it comprises controlling means to co-operate with one or more cutter carriers having a determined angle to carry out from the commencement the eX- tended conical sharpening of one or more pencils at the same time, these cutter' carriers being then displaceable to a more obtuse setting in order to obtain a second conical sharpening of the extremity of the lead. The pencils are thus sharpened with cones of two different angles, an operation which cannot be obtained with machines asiat present in use. i

Furthermore, the machine has for its object to do away with one of the usual crayon,

the shaping of the end thereof, as the cutter by the pivotal action always arrives at the same'place and by this means the crayons or pencils turned out from the machine are sharpened to an exact length.

cutters turn at great speed, such cutters in chalk or pencil forming operations, that is,

The machine is suitable for pencils, challrs, crayons and other similar articles.

The annexed drawing shows by way of example one particular method of carrying the invention into effect.

In the drawing` Fig. 1 is an elevational view of the machine in partial section.

Fig. 2 is a plan view thereof;

Fig.` 3 a sectional elevational View of one of the cutter carriers on a larger scale; and

Fig. l is a view of the cutter showing; the worlt effected by the machine on a pencil, chalk, crayon or the like.

1 represents the frame of the machine on whichis mounted in a suitable manner the spindle 8 driven by a pulley. nAt the ends of the spindle are keyed `cams 6 and 7. The cam 7 controls, through the medium of a lever 5 mounted on a support 3, a rod 1 0 and a series of levers 11, 17 and 18, the movement of a pair of cutter carriers 13 which are coupled together bya link 21. The rotation of said cam is adapted to displace the cutter carriers in a guideway 23, in order to bring them into their operative position and then to eifect the return movement, to allow removal of the two crayons or the like which have been sharpened.

For this purpose the lever 5 is adapted to be pressed against the cam 7 by means of a spring 17 arranged to draw the lever 17 upwardly.

The cam 6 controls, by means of a lever 4. mounted on a bracket 2, a rod 9 and a lever 12 the rotation of the two cutter carriers 13 which are each provided witha pivot 22 secured on a slide 23. rlChe lever l is adapted to bepressed against the cam 6 by means of a spring 12 acting on a lug` 12 secured to lever 12 and adapted to swing;l said lever 12 to the left in Fig. 2. The cutter carriers can thus be set according to any desired angle.

The cam 7 controls acutter holder 14 for the first portion of the sharpening of the crayon, pencil or the like according to the chosen angle, while the cam 6 has for its object to displace the cutter carriers 13 to a more obtuse angle to obtain the sharpening of the extremities as shown in Fig. 1.

Each cutter carrier 13 has a driving pulley 16 which is preferably grooved. The shafts driven by these pulleys each controls one of the cutter holders 14 which is provided With cutters 2O in which diamonds are set. Thecrayons or the like 19 to be sharpened preferably located in a magazine are fed by a distributor into the axial bores or perforations of rotatable pencil supports 19 which are driven by suitable pulleys 19, as shown in Figs. 1 and 2. The shaft 8 is started and the cam 7 controls the two cutter carriers 13 and brings them into their operative position according to the first angular setting. rIhe cutters are turned at great speed and first sharpen the crayons to form the primary cone. As soon as this cone is formed the cam 6` comes into play, and effects the angular displacement of the cutter carriers to a somewhat greater extent causing the cutters to sharpen the extremity of the cone to an obtuse angle as shown in Fig. 4.

VAs soon as this has been accomplished, the cutter carriers are brought back to their initial position to allow the sharpened pencils or crayons to be removed from the machine. Y

It `Willlthus be seen that the pencils are sharpened to tWo formations, the first giving to the extremities an elongated conical form and the second finishing ol:1 t-he conical eX- tremity by a more obtuse cone.

This operation is to prevent the extremities of the crayons, chalks, pencils or the .like becoming broken While being packed and also increases the life of the point.

lVhile I have described What I deem to be the preferred form of my device I do not Wish to be limited thereto as there might be changes made in the arrangement ofvpart-s and their construction Without departing from the spirit of the invention as comprehended yWithin the scope of the appended claims.

What I claim and desire to secure by Letters Patent of the United States of America 1. A pencil sharpening machine of the type described comprising in combination a plurality of rotatable pencil supports, a rotary cutter holder adjacent each of said supports, a plurality of diamond critters mounted in each of said holders, means for dis-A placing said cutter holders transversely with respect to said pencil supports and means for regulating the angle of said cutter holders with respect to said pencil supports for the purpose described.

2. A pencil sharpening machine of the type described comprising in combination a plurality of rotatable pencil supports, a

v guideway transversely disposed with respect to said supports, a carriage mounted in said guideway, a plurality of rotary cutter holders mounted on said carriage', a plurality of diamond cutters mounted in each of said cutter holders, cam controlled means for imparting transverse movement to said carriage and cam controlled means for regulating the angle of said cutter holders with respect to said pencil supports for the purpose described.

3. A pencil sharpening machine of the type described comprising in combination a plurality of rotatable pencil supports, a guideway transversely disposed with respect to said supports, a carriage mounted in said guideway, a plurality of pivotally mounted rotary cutter holders mounted on said carriage, a plurality of diamond cutters mounted in each of said cutter holders, a bell crank adjacent said carriage, a link connecting said bell crank to said carriage, a cam for operating said bell crank, a link interconnecting the said cutter holders, a lever on one of said cutter holders and a cam associated With said lever for imparting rotary motion to said cutter holders for the purpose described.

4. A pencil sharpening machine of the type described comprising in combination a plurality of rotatable pencil supports, a guideWay transversely disposed with respect to said supports, a carriage mounted in said guideway, a plurality of pivotally mounted rotary cutter holders mounted on said carriage, a plurality of diamond cutters mounted in each of said cutter holders, a bell crank adjacent said carriage, a link connecting said bell crank to said carriage, a cam for operating said bell crank, a link interconnecting the said cutter holders, a lever on one of said cutter holders, a cam associated With said lever for imparting rotary motion to said cutter holders and a rotatable shaft interconnecting said ca'ms for the purpose dcscribed.

5. A pencil sharpening machine of the type described comprising in combination a plurality oit' rotatable pencil supports, a guideway transversely disposed with respect to said supports, a carriage mounted in said guideway, a plurality of pivotally mounted rotary cutter holders mounted on said carriage, a plurality of diamond cutters mounted in each of said cutter holders, a bell crank adjacent said carriage, a link connecting said bell crank to said carriage, a cam for oj cr.1ting said bell crank, a link interconnecting the said cutter holders, a lever on one of said cutter holders, a cam associated with said lever for imparting rotary motion to said cutter holders about a vertical axis and pulleys on each of said cutter holders for imparting rotary motion thereto about a horizontal axis for the purpose described.

In Witness whereof I affix my signature.

ROBERT IWARGUERAT.

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